refactor: revert #107 but using enum_dispatch

[bxb100]

hi, @j178 , IMHO I think using enum_dispatch to remove boilerplate code much better, PTAL

[j178]

Thanks for letting me know about enum_dispatch. Before #107 (and in this PR), we had to perform two matches: first from config::Language to languages::Language, and then from languages::Language.<some method> to the actual function implementation. After #107, we only need to perform one match.

There is some boilerplate code, but it seems manageable. We could write a macro to reduce the boilerplate code into a single location. What are your thoughts on this?

[bxb100]

understand, my initial motivation was to eliminate static, if you want to keep this, I'm fine with it